Shumlin sent a letter to U.S. Homeland Security Secretary Janet Napolitano urging her to "reconsider the exercise of your prosecutorial discretion with respect to his case."

Earlier this week, Sen. Patrick Leahy, Sen. Bernie Sanders, and Rep. Peter Welch sent similar letters to Napolitano or to Immigration and Customs Enforcement leaders under her command on Lopez' behalf.

Leahy, chairman of the Judiciary Committee, noted that immigation reform now pending before the Senate would grant farm workers like Lopez a path to lawful status. He told Napolitano "especially in light of pending legislation... I urge you to exercise prosecutorial discretion."

Lopez, 23, acknowledges walking across the U.S.-Mexico border into Arizona six years ago.

"I'm not ashamed to say I came the way many, many other people came here, walking for seven days and nights," Lopez recalled Thursday, a harrowing journey that led him first to Florida and then north to Vermont.

Lopez joined the estimated 1,500 undocumented immigrants who milk cows on Vermont dairy farms, a labor force many farmers consider essential to their survival because they fill jobs no one else will take.

In August, 2011 in Middlesex, Lopez was a passenger in a car pulled over by state police for speeding, and was questioned about his immigration status.

Troopers alerted federal agents who picked up Lopez and initiated processing for deportation.

But in the intervening two years Lopez has become the face of the Migrant Justice advocacy group. The group persuaded Shumlin to change state police policy governing traffic stops and immigration queries, and this spring lobbied the Legislature to pass a law granting undocumented workers access to a driver's license for the first time.

"He is a leader who has worked tirelessly to engage and educate state officials regarding migrant farm workers and his efforts have contributed to the enactment of new state laws and policies that will improve the lives of these hardworking members of our farming community," Shumlin wrote Napolitano.

Shumlin said the case points out the need for federal immigration reform.

Lopez said he is hoping strong support from the state's top elected leaders will help win a reprieve - or at least an extension - though he seemed resigned to the possibility he will be deported to Mexico.

He said his father, uncle, nephews and cousins are all in the U.S. but his mother still lives in Comitan, Mexico near the southern border with Guatemala.

"It's sad," he said, "being kicked out will really feel sad. I've been living and working here for over six years."

Were he able to speak directly with Napolitano, Lopez said he would explain how deportation separates families. "I think it is not correct," he said.

Leahy spokesman David Carle said Thursday afternoon that Napolitano has not yet responded to this week's letters.

"The immigration system is broken, but the law is still the law, and requests like this are difficult and rarely granted," Carle cautioned.

Natalia Fajardo, also part of Migrant Justice, said her group is hearing reports of stepped up efforts by the U.S. Border Patrol in recent weeks to identify undocumented dairy farm workers in Vermont.

"That is simply not true," said John Pfeifer, chief of the Border Patrol office in Swanton.

Pfeifer said no spike in enforcement had occurred involving farm workers and released statistics Thursday showing a total of nine Mexican nationals tied to the dairy community were processed for immigration violations in the current fiscal year, up from seven in the previous year.

The Swanton sector is responsible for the region from Ogdensburg, N.Y. across Vermont and New Hampshire to the Maine border.